Stabilization of oils



Patented Feb. 17, 12

- s'rmza'rrorz or ons Siey Masher, New; York, N. Y., assignor to Mer Fotion Incorporated, New York, N. Y., a corporation of New York No Drawing. Application September 23, 1938,

The present invention relates to the stabilization of organic products subject to oxldative deterioraition,.and it particularly relates to the stabilization of such products as hydrocarbon oils, paint oils, essential oils, rubber, glyceride oils, etc., by treating them with the concentrated water soluble extract of cereals and grains, and. particularly .when the stabilizing activity of that extract is increased in potency by heattreatment.

It has been found that certain materials such as fats may be treated by adding thereto oil soluble antioxidant materials; such as the crude vegetable oils, lecithin, .etc. These materials. may also be treated with the substantially oily seed materials such as crushed seasame seed,

crushed peanuts,- etc., wherein free oils is released iollowing the macerating or grinding process. o

. The use of the substantially oily or oil soluble materials described above, in ,frequent cases does not give sufllcient protection over a prolonged period of time. In addition, a great many products subject to deterioration are processesd at elevated temperatures such as where the hydrocarbonoils are refined at temperatures in excess of 160 0., where the glyceride oils are deodorized at temperatures in excess of 375- R, where L (ems-250) without departing from the scope and spirit of the present invention. e

In accomplishing the above objects, it has been found most satisfactory to incorporate in products subject to deterioration the water soluble extract in concentrated form of the cereals and grains such as corn, barley, oats, hominy, tapioca, rye, rice, wheat, buckwheat, etc. The preferred material for extraction contains less than 0.75% total phospho'lipins and less than 10% of glyceride content and it is preferably in a fine state of division. The cereal extract derived from oats and maize preferably in raw unbleached condition, dr'y milled and in flour or divided form gives the highest yield of stabilizing activity and is far more desirable. The cereals produce the most acceptable extract because of their low oil content which seems to enhance the production of a substantially oilfree extract as contrasted to the high oil contaming materials in which the antioxidants are not as readily susceptible to water extraction.

Although the water soluble extract may be prepared in many different fashions and may be added at many stages to products subject to deterioration, it has been found niost satisfactory to prepare such extract by grinding or: dividing the cereal and then submerging it in or extractis to be used in the product or processing of the organic material to be stabilized.

ing the same and otherproducts subject to oxidative deterioration, the stability of which products will not be decreased by processing at ele- Stilljurther objects and advantages will apf lowing a thorough mixture, the water may he removed without substantially decreasing the oil solpear from the more detaiied description set I forth below, it .being understood, been, that-jthis more detailed description is given by way.

01' illustration and explanation only,; and not thereinlmay be made activity of the extractby vacuum distillation,

by drying, at room temperature, or in a reducing atmosphere, etc.,an d the extract will take [the form of a brown pasty material or a dry.

powdery rayish material, generally hygroscopic in character. 3

s The extracts may not be completely soiihile in the paint or hydrocarbon oil to be stabilized, but this will not decrease their efliciency as stabi- Wherfe -desired, the 'insoluble material maybe ing it with water or an aqueous material which filtered "ofi preferably following heating.

excess of 250 1''. and desirably in excess of 350 1".

" This extract, in contradistinction tcthe crude ,vegetable oils, lecithin, etc., is not only unaflected by heat treatment, but is actually activated under conditions of heat. When the extract is utilized in organic products that are'normaliy processed at high temperatures, or to which a high temperature treatment may normally be applied, minute percentages of the extract will give a marked stabilizing action.

lhe hydrocarbon or the paint oils, such as lin-' seedoil. or medicinal oils, such as, cod liver oil.

may be treated with the concentrated water soluble extract of the cereals to markedly improve xtheil' stability, and the stabilizing eilfect is particularly observed when the extract is heated in the oil to temperaturesin excess or 250 F.,and

I desirably in excess of 350 F..

- Example I Linseed oil was treated with 0.1% he concentrated water soluble extract of drymilied maize. flour, said maize flour having a lecithin contentof less than 0.5%. The oils were tested on. the so-called Swift stability apparatus by bubbling air through samples of those oils at 208? F. until rancidity was observed as determined both .org'anoieptically and. by peroxide values, the hours given indicating the. time required before 'rancidity could be detected.

. Hours Control linseed oil 3, Linseed oil containing 0.2% of t e extra t. .l Linseed oil ,containing'0.2% of e extract.

the entire mixture having been-heated to 400 F, forminutes 16 Example 11 Cod liver oil was tested under similar circum stances- Control cod liver oil 1% God liver oil plus 0.2% of the concentrated water extract of maize flour 4 A Cod liver oil plus 0.2% of the concentrated water extract of maize flour heated in the oil to 400 F. for 0 minutes 1-3 Although in the experiments above indicated,

0.2% of the extract was utilized, otherproportions varying from 0.05% to 2% of the extract may be employed, to obtain marked stabilizing activity.

Although, the concentrated water soluble extract is preferred for use with the organic materials described herein, where advisable, the'unconcentrated water soluble extract of the cereals may also be employed.

Oils, such as the hydrocarbon oils, glyceride oils, essential oils, .etc. "are subject to rapiddeterioration when in emulsified form such as the medicinal cod liver oil emulsions, petrolatum emulsions, etc. The use of the water soluble extract in the disperse water phase will materially retard such deterioration.

Example III A regular mineral oil emulsionwas prepared with 2% of water by weight to obtain a water in oil, emulsion. "To one lot of samples 2.0% or the water extract of oat flour was added to the water before emulsiflcation. The samples Hoursp 2,273,002 in theoil being stabilizedlto a temperature in were set aside at room temperature in the dark.

5 1 month 3 months i '5 months Nb um- Slightly 0a.. Definite oxidised Very bad.

ment. odor and taste. Treated.... 0. K Onlgveryslightly Little worse than o inodor, taste 3 months, much 0.1:. superior to no a treatment.

Surprising the extract is frequently more effective the. the original cereal from which the extract is bbtained, even though the residue of some stabilizing properties.

Example IV a made-- p was ;heatedto 400 F. for 0 minutes and then used in the manufacture of soap in the usual way; Y B. With cocoanut oil containing the concen trated waterextract of 5% of oat flour the cereal following the extraction still retains A. With cocoanut-oil having been previously "against the weight of the oil. the oil conthe extract having been heated to 400? 1". for 0 minutes before manufacturing into soap;

'ilour against the weight of the oil, the oat flour having been heated in the oil to 400 .1". forO minutes before manufacturing into s ap.

lisht. v

- Rancidity observed after 7 I Days Soap SoapC result of which charring is produced when the extractis heated in the presence of the oxidizable .unaterial. Regardless of the charring, however,

50" the extract, as indicated in the examples, be-

comes increasingly eii'ective at temperatures in excess of about 250 F; and particularlyat 400 F. or. above so that it may readily be used in connection with materials that are normally processed athigh temperatures and where other antioxidants, and particularly the oil soluble antioxidants would be inactivated or at least substantially reduced in activity.

Moreover; the extracts described, whether evaporated to dryness or not, are frequently more effective than the unextracted cereals from which they were removed, and after being in contact I with the oxidizable materials for long periods, the treated materials retain their improved status if the original cereal J The soap followingemanufacture was held at room temperature exposed to-the air in indirect "The concentrated extract obtained contains a Y certain' amount of carbohydrate material .as a

'C. With cocoanut oil containing 5% of oat are not deactivated at elevated temperatures, but even become more active at temperatures as high as 400 F., for example, and they have more continued potency for longer periods of time.

Example V I Reflned cottonseedoil was prepared V The oils were tested on the Swift stability apparatus. 1 a

Rancidity observed after 20 I Hours 011 A. 11 Oil B 14 on c 26 I Example VI 28 A. Untreated; heated to 400 F. for 0 minutes;

B. By heating the cottonseed oil to 400 F.

for 0 minutes and then adding 0.5% of -the concentrated water extract of oat flour; e

C. with 0.5% of the concentrated -water extract of oat flour heated in the oil to' 400 F. for 0 minutes.

grams of lard were prepared,-

A. Untreated, heatedto400 F.- ior 0 min-' utes;

B. With 0.4 gram of oat fijour heated in the oil to 400 F. for 0 minutes; C. with 0.02 gram of the concentrated water extract of oat flour (obtained from 0.4 gram of oat flour) heated in the oil to 400 F. for 0 minutes. r

j The lar'ds were tested on the Swift stability apparatus referred to above.

Rancidi'ty observed after- Hours 0 LardA 1% Lard B 4 Lard C 8% It has also been observed that the relative rate I of activation under conditions of heat treatment .is far greater when the extract is utilized than when the proportionate amount 0! the unextracted cereal is utilized. For. example, when maize flour is activated under conditions 01' heat in an oxidizable on, its potency mu be increased 5 ,to only a small portion oithe increase observed .ticularly when heat activated, not only-to the tial oils, rubber, etc. Also in the sizing or tex- 1 tiles and fabrics and in the manufacture of paper,

when the extract of that cereal used tionate amounts is similarly heated.

.The extracts described may be applied, parin proporpaint oils, other glyceride oils, shortening, hydrogenated fats. etc., but also to the hydrocarbon oils, pharmaceutical preparations, creams, essenboard, etc., where the sizing baths comprise sulphonated oils, soaps, etc., the extracts may. be employed to retard oxidation oi the fabrics, their pigments, paper, etc. The extracts may be utilized either for addition to the'sulphonated oils, 05

soaps, etc., for example, and preferable heat activoted, or they may be added directly to the aqueous sizing baths so that the water soluble antioxidant material penetrates the fabric or paper product.

Although the unconcentrated extract maybe utilized, it is preferable for purposes of this invention to use the concentrated or dry extracts after removal of the aqueous solvent. -Where water is normally used in the processing of or-= 1 ganlc materials, there may be employedeither the concentrated extract or the unconcentrated extract in a dilute iorm.

'Example VII Where coflee is heated or roasted at a high temperature and water applied to the beans to :cool and hydrate them and while the beans are at a temperature in excess of 400 F., water may be applied containing a small portion of the water soluble extract of a cereal.

Under these conditions the heat of the roasting would normally inactivate the oil soluble type tion of a substantial portion of the oil, the residue.

may be extracted and the extract so obtained may be employed as an antioxidant the hydrocarbon oils, other glyceride oils, paint oils,

essential oils, etc., and particularly activated un--v der conditions of heat.

The cereals and to a greater degree the de-oiled or low oil containing .seeds even without extraction of the water and/or alcohol soluble portion exhibit much more marked antioxidant activity after being subjected totemperatures in excess of 250 F. and more desirably in excess of 400 1". and particularly in the presence of the oxidizable material.

However, in accordance with the present my vention it.is preferred to use the water extract of such materials. 1

P Example VIII.

Ground sesame seeds containing about:65% of oil "were subjected to extraction with hexane. The residue following the extraction contained 0.2% of oil. Cod liver oil was prepared as follows A. Untreated o B.'Con'taining 0.5% of the: concentrated water extract of the de-oiled sesame residue 0C. Containing 0.5% of the concentrated water extract of the tie-oiled sesame residue heated in the oil to'400 F. V

D. Containing 1.0% of th de-oiled sesame residue -E. Containing 1.0% of the de-oiled sesame residue heated in the oil to 400 F.

The cod liver oil samples were held at F. in the dark until rancidity as determined by peroxide values, was observed.

Rancidity observed after I Hours Sample A 18 Sample B 29 Sample C 48 Sample D-.- 22 Sample E 30 Among other less preferred materials are the substantially dry seeds'capable o1 powdering withoutreleasing tree oil during a macerating process. For example, such seeds as cottonseed.

or soya may be employed Particularly after the expression or extraction oi the glyceride oils pon paratus above referred to tained therein. Care must be exercised to remove all possible water insoluble materials when.

- preparing, for example, the water soluble extract. Any milky suspension obtained during careless or incomplete water extraction will contain water insoluble materials including glyceride oils. It is desirable to hate the extract substantially free of water insoluble materials such as would be present in a milky suspension: and which water insoluble materials would prove detrimental to the preparation of the extract.

. Example IX A paint oil mixture'of 50% linseed oil and 50% soya bean oil was prepared as follows: 3

A. control s W B. with 0.25% of the concentrated water extract Theoils were: tested 'on the Swift Rancidity observed after 011 A 12 one 1 on c: s 31 'I heextracts of the seeds differ from the extracts of the cereals in that the seed extracts are considerably higher in carbohydrate content, will of the c'ereals.

In addition .to using water as the extracting medium, alcohols may be also employed, although they are less desirable Among the may be used are ethyl and less preferably methyl, butyl, propyl, and accepted denatured types of alcohols. In certain cases itis also possible to use polyhydric alcohols such as glycerol or other glycols','but as a general rule these polyhydric alcoholsar not particularly' satisfactory. The alcoholic extracts may desirably be subjected to aaraoea taining water extractable carbohydrates.- and, to

a lesser degree, 'phospholipins in combination with such carbohydrates may also be employed.

By paint oils is meant particularly the sub- 'stantially drying oils such as linseed. tung. soya,

sunflower, poppy, etc., but the same procedures may be used for other glycerides which term includes the entire class of animal and vegetable oils and-fats and compositions containing them.

By hydrocarbon oils is meant any of the homologous series such as gasoline, kerosene. hexane, petrolatum oi1s,-etc., and also the hydrocar bon type of oils such as rubber, the terpenes. pharmaceutical creams, etc.

By essential oils is means the flavoring oils such as oil of lemon, orange, peppermint, wintergreen,

stability apchar and will discolor oils particularly under 40 conditions of heat more readily than the extracts an oil solvent extraction so as to remove suchof theglycerides as happen to.be present. This will not materially alter th effectiveness of thextract and particularly where the maximum water solubility is required, will be of distinct advantage. Mixtures of the alcohols and water, of course, may be employed. Oil extracting solvents, such as hexane should not be employed. The alcohol and water types ofsolvent are included by free and starch free antioxidant material ex-. tracted by a solvent selected from the group conthe expression XOH where X represents hydrog gen, or a low molecular weight aliphatic group.

- Although the cereals are always preferred in divided form and although in certain cases the.

oil bearing seeds and nuts. the oil content of which has been reduced to below l0%, may be 'sutilized for extraction, it is possible in some cases the perfumes, etc.

The heat treatment for purposes-of activation I referred to herein should, as indicated, be desirably carried out in the presence of the oxidizable substance and should be carried out at a temperature in excess of 250 F. The higher the temperature up to about 450 F., the greater will m V the increase in antioxidant activity and the proportionate increase will be far greater at tern perature ranges in excessof 350 F. For example.

when the heat treatment is carried out at 400 F.. to 450 F., a much greater increasev in antioxidant effect will be produced than where the heat -treatment is only 250 to 300 F. For this reason it is desirable wherever practicable to subject the oxidizable material to a heat treatment of about 400 F. to 450 F. with a small amount of the stabilizing material described herein.

By the expression seeds,

being preferred and giving a more desirable and effective. .antioxygenic material.

'The present application is; a co part of prior applications, Serial No. 15,307, filed .April 8, i935, and Serial No. 135,169 flied April 5, i937.-

alcohols that Having thus set forth my invention, I claim: 1. A composition containing. a substantially "unoxidized 011, said oil being subject to oxldative deterioration upon standing or heating in the presence of air and said composition containing I sumcient substantially unoxidized oil to produce deterioration of the composition upon oxidative' deterioration of said oil, said oil being selected from the group consisting of the non-volatile fixed slyceride oils and fats of vegetable and animal -origin, said composition containing the reaction product of a relatively small amountv of an oil insoluble, carbohydrate containing fiber sisting of water and alcohol from a finely divided raw-unbleached low oil andlow lecithin containing cereal flour,'said antioxidant material;

4 having been dispersed throughout thebody of the composition, said reaction product having been formed by heating said'antioxidant material with the oil at a temperature of at least about 250 F.

2. a composition containing a substantially unoxidized linseed oil, said linseed oil being subto combine w'ith these materials or to use alone other beans such as the cacao bean, ;from

rials have been extracted or expressed, or thew sl a large proportion of the oily andfi rattymatercoffee bean'in unroasted condition, both of which materials should preferably be in powdered'formbefore extraction. Other similar materials con"- iect to oxidative deterioration upon standing or heating in the presence of air and said omposition containing sufflcient substantially unoxi-' dized linseed oil to produce deterioration of .the

composition upon oxidative deterioration of said 011, said composition containing the reaction .75 product of a relatively small amountof an oil is included the 1 cereals and also the substantially de-oiled oil: containing seeds and nuts, the cereals, however,

ntinuation in' insoluble, carbohydrate containing fiber free and starch free antioxidant material extracted by a solvent selected from the group consisting of water and alcohol from the cereals, said antioxidant material having been dispersed throughout the body of the composition, said reaction product having been formed by heating said antioxidant material with the oil at a temperature of at least about 250 F.

3. A substantially unoxidized linseed oil normally subject to oxidative deterioration and development of rancidity upon standing or heating tween the antioxidant material and the composition and then heating to a temperature in excess of 250 F., whereby said composition and said in the presence of air, said oil containing the a reaction product of 0.2% of the concentrated fiber and starch free carbohydrate containing water soluble extract of dry milled maize flour,

said extract being dispersed throughout the body of the oil, said reaction product having been formed by heating said antioxidant material with the oil at a temperature of'at least about 250 F.,

whereby said oil has been rendered highly resistant to oxidative deterioration.

' 4. A substantially unoxidized refined mineral oil emulsion normally subject to oxidative deterioration upon standing or heating in the presence of air, said emulsion containing the reaction product of about 2% of concentrated fiber and starch free carbohydrate containing water extract of oat flour, said extract being distributed throughout the body of the emulsion, said reac-v tion product having been formed by heating said antioxidant material with the oil at a temperature of at least about 250 F., whereby said emulsion has been rendered highly resistant to oxidative deterioration.

5. The process of stabilizing composition containing substantially unoxidized oils, said oils being subject to oxidative deterioration and being present in sufiicient quantity in the composition to produce deterioration of the entire composition upon oxidative deterioration of the oil therein, said oil being selected from the group all contained therein are both rendered highly resistant to oxidative deterioration.

6. The process of stabilizing compositions conwith and contact betweenthe antioxidant maconsisting Ofythe non-volatile fixed glyceride oilsand fats of animal and vegetable origin. said process consisting of dispersing a small quantity of an oil insoluble, carbohydrate containing fiber free and starch free antioxidant material exterial and the composition and then heating to a temperature in excess of 250 F'., whereby said composition and said 011 contained therein are both rendered highly resistant to oxidative deterioration, said antioxidant material consisting of the extract of the oil-depleted, powdery seeds obtained by the use of a solvent selected from the group consisting of water and low molecular weight aliphatic alcohols.

7.-"I'he process of stabilizing compositions containing substantially unoxidized oils, said oils being subject to oxidative deterioration and being present in sufiiicent quantity in the composition to produce deterioration of the entire composition upon oxidative deterioration of the oil therein, said oil being selected from, the group consisting of the non-volatile fixed glyceride oils and fats of animal and vegetable origin, said process'consisting of dispersing a small quantity of an oil insoluble carbohydrate containing fiber free and starch free. antioxidant material extracted by a solvent selected from the group consisting of waterand alcohol from a finely divided raw unbleached cereal flour in said compositions so as to assure thorough mixture with and contact between the antioxidant material and the ncomposition and then heating to a temperature tracted by a solvent selected from the group consisting of water and alcohol from finely divided raw unbleached seeds in said compositions so as to assure thorough mixture with and contact beof about 400 F. whereby said composition and said oil contained therein are both rendered highly resistant to oxidative deterioration.

SIDNEY MUSHER. 

